Making glass sheet or plate



0/7//5 l VT May 27, 1941.

INVENTOR. Everett I, Cook ATTORNEYS -Pnenied May 21,1941A UNITED STATES PATENT GFI-ICE mmonssssnsnoamra' smacnarmmu `Ammann reu-nary zi, ma, seein No. 191,595

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This invention relates to the making of glass Y very large expensive equipment is needed to grind,

and polish the glass surfaces. This equipment is, in some instances, of exceedingly great length, requires the use of much power and tremendous quantities of water. The equipment is not only.l

initially expensive but is expensive to maintain and operate. l

'I'he principal object of this invention is to provide improvements in the art of making plate or sheet glass by means of which the glass Burfaces are given a highly polished lustrous nish.. 'Ihe method contemplated is not a complicated one from the standpoint of the mechanical or physical steps involved, and the method may be carried out by a relatively small, inexpensive and cheaply operated apparatus. Generally, the invention involves what may be termed steam polishing the glass surfaces, this beingaccomplished as the glass sheet moves from a supply of molten glass, and, contrary to the practice followed heretofore, as mentioned above, the treatment is given to the surfaces of the glass prior to complete solidiilcation.

forebays. The forebay is provided with an voutlet or spout, the dimensions ot which may be varied and controlled by adjustable members I, and in the outlet is an element which may be termed an arbor l, the lower .end of which preferably is of tapering form to correspond to the outlet.

'lhis arbor'may be arranged for vertical adjustment, and the. means for accomplishing this, as shown herein, takes the form of a threaded shaft l upon which is a, worm gear I having a threaded engagement therewith, the worm -gear resting v in a bracket 0 and for turning the worm gear is a In the accompanying drawing, apparatus is shown somewhat diagrammatically for carrying out the invention, it being understood that the particular illustrations used are demonstrative only and that the invention is not limited to the particular structures, although these structures ,I

are specifically described below.

Fig. 1 is a view partly in cross section illustrating a receptacle and forelay for molten glass,

an outlet for the glass, and means for treating a sheet of glass moved therefrom.

lilg. 2 is a view similar to Fig. 1 illust-rating a modined form. Fig. 3 is a, view similar to Fig. 2 illustrating another modified form.

Fig. 4 is a view illustrating a further modined form of device for polishing a moving sheet of glass.

Fig. 5 is a view illustrating a still further modliled form of device for polishing the surfaces of a moving sheet of glass. i

A glass furnace is generally illustrated at i provided with a forebay 2, which may be closed 1, between driven pressure rolls. There are two motor II with a worm Il.'` 'I'he raising and lowering of the arbor and alsoadiustment of the pieces l varies the spacing between the outlet walls of the arbor for determining the thickness of the sheet of glass which issues therefrom.

As illustrated in Fig. 1, the forebay and arbor are adjusted for the issuance of two sheets of glass 2l and 2|,together with an intermediate binder 22. This forms a so-called safety glass -with the binder being united with the sheets to Prevent the same from shattering. Thisbinder may be introduced through one or more pipes l I2 leading into'the hollow interior I3 of the arbor, the hollow interior of the arbor opening at its lower end as illustrated at I4. The flow of the binder from the arbor may be determined by gaseous pressure transmitted into the interior of the arbor through a pipe i5 and this pressure may be' above or below atmospheric to` obtain the desired control. As illustrated, the substance is piled up, so= to speak, inside the arbor, the upper surface being indicated at Il. This par-` ticular forebay and arbor construction has been selected for use in demonstratingthe present invention, although it-is to be understood that this invention may be used with other structures from which a sheet of glass may' be caused to issue from a supply of molten glass. f

The two sheets of glass with the intermediate binder .arebrought together, `as shown in Fig.

rolls 2B and 26 on one side of the composite sheet and two rolls 21 and 28= on the opposite side. 'I'hese rolls may all be driven by a motor 29 whichhas a shaft 30 operably connected with o!! by a suitable gate 3, and there may be a screen 4 between the body of the glass inthe furnace the rollers as indicated. 'I'he set of rollers 21-28 may be adjusted toward and away from the rollers 25-28 to accommodate Ifor variations in thickness of the done by connecting therollers 21 and 28V to a rod 3| arranged to be shifted,x by a worm gear 32 threaded'on the shaft 3| and positioned in ay bracket l! and turned by aj motor u having a composite sheet: this may be ment past and in close proximity' to but out of actual contact with an element comprising soft carbon containing water whereby the heat from the glass generates steam to set up a steam lm between the surfaces of the glass and the carbon element to give the surfaces a polished nish.

4. In the art of producing glass in sheet or plate form, ,the steps of causing glass in sheet or plate form to gravitate through a shape-dening opening from a supply of molten glass with movement substantially longitudinally, presenting to surfaces of the sheet or plate substantially without pressure a moving element comprising a heat resisting substance containing water whereby the heat from .the glass generates steam to set up a steam lm between the surfaces of the glass and said element to prevent substantial contact and to give the surfaces a polished finish.

5. An apparatus for making sheet or plate glass which comprises, a receptacle for molten glass, an outlet means adjacent the bottom of the receptacle for owing of a stream of glass in a downward direction in the form of sheet or plate from the receptacle, means for guiding the sheet with straight line movement, and an absorbent element containing a liquid positioned in close prox,-

imity to the sheet at a point where the glass is plastic but out of direct contact therewith for the generation of steam by the heat of the glass, whereby a film of steam is set up between the surfaces of the glass and said element for giving the surfaces a polished nish.

6. An apparatus for making sheet or plate glass which comprises, a receptacle for molten glass having an outlet opening in its bottom with dimensions substantially corresponding to the sheet or plate, for the owing of molten glass downwardly therethrough in plate or sheet form, means having a surface of a soft carbon positioned for the passage of the plate or sheet of glass past the same with straight line movement and in proximity thereto but out of direct contact therewith and while the glass is plastic, and means for wetting the carbon, whereby the heat of the glass generates steam so that a film of steam is set up between the glass surfaces and the carbon to give the glass surfaces a polished finish.

7. An apparatus for making sheet or plate glass which comprises, a receptacle for molten glass having an 'outlet opening in its bottom with dimensions substantially corresponding to the sheet or plate, for the flowing of molten glass downwardly therethrough in plate or sheet form, means having a surface of a soft carbon positioned for the passage of the plate or sheet of glass past the same with straight line movement and in proximity thereto but out of direct contact therewith and while the glass is plastic, means for wetting the carbon whereby the heat of the glass genline, and a set of driven rollers having soft carbon surfaces positioned on opposite sides of the sheet or plate and located to lie in proximity to the sheet or plate but out of direct contact there with while the glass is plastic, and means for wetting the carbon for the generation of steam by the heat of the glass to set up a film of steam -between the glass and the surfaces of the rollers.

9. An apparatus for making sheet or plate glass which comprises, means for issuing glass in the form of sheet or plate from a supply of molten glass with movement longitudinally, an endless belt operating over rollers having a surface of soft carbon, said belt being positioned so that a run thereof lies in proximity to but out of contact with surfaces of the sheet or plate while the glass is plastic, and means for wetting the carbon surface of the belt for the generation of a nlm of steam due to the heat of the glass between the glass surfaces and the carbon film for steam polishing the surfaces of the glass.

10. An apparatus for making sheet or plate glass which comprises, means for issuing glass in the form of sheet or plate from a supply of molten glass with movement substantially longitudinally, and a stationary element having a-surface of relatively soft carbon positioned in proximity to but out of direct contact with surfaces of the sheet or plate while the glass is plastic, and means for wetting the carbon for the generation ofa nlm of steam by the heat o'f the glass between the surfaces of the sheet or plate and the surfaces of carbon for steam polishing the surfaces of the glass.

11. In the art of producing glass in sheet or plate form, the steps of causing molten glass in sheet or plate form to issue from a supply of molten glass with movement longitudinally, passing the sheet or plate while in a plastic condition with a substantially straight line movement in proximity to a moving element of heat resisting absorbent substance moistened with a liquid and which liquid vaporizes to set up a vapor film` between the surfaces of the glass to prevent subv stantial contact between the surfaces of the glass and said element and to give the surfaces of the glass a polished finish.

' `EVERE'IT J. COOK. 

